3-D numerical simulation of density currents’ spreading on the slope

Many experiments,the analytic solutions and the numerical simulations are conducted to investigate density currents.But turbulence is usually neglected or sometimes considered by using the simple turbulence model among them.In this paper,a 3-D mathematic model with the explicit algebraic Reynolds stress/fluxes turbulence model (EARSM) is developed to simulate the anisotropic buoyant turbulent flows.The collocated,unstructured finite volume method is applied to solve the Navier-Stokes equations and the pressure coupling is treated using the SIMPLEC algorithm.The case of 3-D density currents' spreading on the slope with 15 angle is simulated Results show that the spreading velocity of the front computed at the present is consistent with the experiments.Also,the present model successfully reproduces the flow characteristic and the configuration of density currents,and shows its good convergent performance.The model can be extended to simulate density currents' spreading in natural environment with complex geometry and topology.